1. Field of the Invention
This invention lies in the field of tiltable valves for pressurized containers, especially valves adapted to dispense viscous fluids, and also to improved moveable cup members for such valves.
2. Description of the Prior Art
In the art of aerosol valves, it has heretofore been appreciated that tiltable valve assemblies can employ among their components a moveable cup member (see, for example, Ewald U.S. Pat. No. 3,547,405). Characteristically, in such prior art aerosol valve assemblies, such a moveable cup member has served as a means for introducing turbulent type flow into the fluid stream being dispensed which is desirable in order to produce a homogenous aerosol comprised of material being dispensed in admixture with the pressurizing propellant in a vapor phase.
When, however, it is desired to dispense a highly viscous fluid, a completely different type of fluid flow through such a valve structure during dispensing is desired and is even necessary for operability reasons. For a viscous liquid, fluid flow through such a valve structure should be laminar in type and not turbulent.
In turbulent flow, it is typical in the art to utilize small clearance passages particularly in the region of the moveable cup member which then feeds into a relatively larger passageway out of which the aerosol is finally vented. When a tiltable valve structure containing such small passageways in the region of the moveable cup is used for an attempt to dispense a viscous fluids, it is discovered that severe problems exist owing to the difficulty of passing a viscous liquid through such narrow passageways. As a practical matter, it is found that narrow passageways in the region of the moveable cup member produce a generally inoperative valve structure for the dispensing of highly viscous fluids.
In order to provide a valve assembly for use with an aerosol type dispensing container from which a viscous liquid is to be dispensed, it is desirable, then, to have cross-sectionally very large and longitudinally very short passageways through which such a viscous liquid must pass to be dispensed.
The achievement of a tiltable valve assembly which employs a moveable cup member with extremely large passageways not only in the region of the moveable cup member, but also in the region of the valve aperture formable between the moveable cup member and a gasket, combined with the necessity to have a positive valve sealing action when the valve structure is in a closed configuration, represents a problem in the prior art which so far as is now known has not been previously solved.